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1.
Cell ; 187(14): 3541-3562.e51, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38996487

RESUMEN

Analyses of ancient DNA typically involve sequencing the surviving short oligonucleotides and aligning to genome assemblies from related, modern species. Here, we report that skin from a female woolly mammoth (†Mammuthus primigenius) that died 52,000 years ago retained its ancient genome architecture. We use PaleoHi-C to map chromatin contacts and assemble its genome, yielding 28 chromosome-length scaffolds. Chromosome territories, compartments, loops, Barr bodies, and inactive X chromosome (Xi) superdomains persist. The active and inactive genome compartments in mammoth skin more closely resemble Asian elephant skin than other elephant tissues. Our analyses uncover new biology. Differences in compartmentalization reveal genes whose transcription was potentially altered in mammoths vs. elephants. Mammoth Xi has a tetradic architecture, not bipartite like human and mouse. We hypothesize that, shortly after this mammoth's death, the sample spontaneously freeze-dried in the Siberian cold, leading to a glass transition that preserved subfossils of ancient chromosomes at nanometer scale.


Asunto(s)
Genoma , Mamuts , Piel , Animales , Mamuts/genética , Genoma/genética , Femenino , Elefantes/genética , Cromatina/genética , Fósiles , ADN Antiguo/análisis , Ratones , Humanos , Cromosoma X/genética
2.
Sci Rep ; 14(1): 16221, 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39003385

RESUMEN

In East Africa, community-based conservation models (CBCMs) have been established to support the conservation of wildlife in fragmented landscapes like the Tarangire Ecosystem, Tanzania. To assess how different management approaches maintained large herbivore populations, we conducted line distance surveys and estimated seasonal densities of elephant, giraffe, zebra, and wildebeest in six management units, including three CBCMs, two national parks (positive controls), and one area with little conservation interventions (negative control). Using a Monte-Carlo approach to propagate uncertainties from the density estimates and trend analysis, we analyzed the resulting time series (2011-2019). Densities of the target species were consistently low in the site with little conservation interventions. In contrast, densities of zebra and wildebeest in CBCMs were similar to national parks, providing evidence that CBCMs contributed to the stabilization of these migratory populations in the central part of the ecosystem. CBCMs also supported giraffe and elephant densities similar to those found in national parks. In contrast, the functional connectivity of Lake Manyara National Park has not been augmented by CBCMs. Our analysis suggests that CBCMs can effectively conserve large herbivores, and that maintaining connectivity through CBCMs should be prioritized.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Herbivoria , Animales , Conservación de los Recursos Naturales/métodos , Tanzanía , Elefantes/fisiología , Dinámica Poblacional , Densidad de Población , Jirafas/fisiología , Equidae/fisiología
3.
Phys Rev Lett ; 132(24): 248402, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38949331

RESUMEN

One of the key problems in active materials is the control of shape through actuation. A fascinating example of such control is the elephant trunk, a long, muscular, and extremely dexterous organ with multiple vital functions. The elephant trunk is an object of fascination for biologists, physicists, and children alike. Its versatility relies on the intricate interplay of multiple unique physical mechanisms and biological design principles. Here, we explore these principles using the theory of active filaments and build, theoretically, computationally, and experimentally, a minimal model that explains and accomplishes some of the spectacular features of the elephant trunk.


Asunto(s)
Elefantes , Modelos Biológicos , Animales , Fenómenos Biomecánicos
4.
Proc Natl Acad Sci U S A ; 121(29): e2401814121, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38950358

RESUMEN

Protected areas can conserve wildlife and benefit people when managed effectively. African governments increasingly delegate the management of protected areas to private, nongovernmental organizations, hoping that private organizations' significant resources and technical capacities actualize protected areas' potential. Does private sector management improve outcomes compared to a counterfactual of government management? We leverage the transfer of management authority from governments to African Parks (AP)-the largest private manager of protected areas in Africa-to show that private management significantly improves wildlife outcomes via reduced elephant poaching and increased bird abundances. Our results also suggest that AP's management augments tourism, while the effect on rural wealth is inconclusive. However, AP's management increases the risk of armed groups targeting civilians, which could be an unintended outcome of AP's improved monitoring and enforcement systems. These findings reveal an intricate interplay between conservation, economic development, and security under privately managed protected areas in Africa.


Asunto(s)
Animales Salvajes , Conservación de los Recursos Naturales , Sector Privado , Turismo , Conservación de los Recursos Naturales/métodos , Animales , África , Humanos , Elefantes , Aves , Parques Recreativos
5.
PeerJ ; 12: e17535, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38854797

RESUMEN

With the escalating challenges in captive elephant management, the study of elephant reintegration emerges as a pivotal area of research, primarily addressing the enhancement of animal welfare. The term 'reintegration' refers to the process of rehabilitating captive elephants to a natural system, allowing them to roam freely without intensive human intervention. There is a relative paucity of research addressing the behavioural adaptations post-reintegration, despite reintegration of over 20 elephants across various fenced reserves in South Africa. Our study centres on two distinct herds of reintegrated African elephants, monitoring their movement patterns in two South African reserves over a 57-month period post-release. The primary goal of the study was to establish whether the flexibility and adaptability of movement behaviour of reintegrated elephants can be considered as one of the indicators of determining the success of such an operation. The second aim of our study was to investigate if the reintegrated elephants demonstrated an adaptability to their environment through their hourly, daily, and seasonal ranging patterns after a period of free roaming that exceeded 4 years. Our findings indicated that reintegrated elephants, much like their wild counterparts (movement based on literature), displayed notable seasonal and diurnal variations in key movement parameters, such as utilisation distribution areas and reserve utilization. These patterns changed over time, reflecting an adaptive shift in movement patterns after several years of free roaming. Notably, the trajectory of changes in movement parameters varied between herds, indicating unique adaptation responses, likely resulting from differences in the reintegration process (familiarity of reserve, season of release, presence of wild elephants). Although our study is constrained by the limited number of reintegrated herds available for analysis, it underscores the potential of captive elephants to successfully adapt to a free-living environment, emphasising the promising implications of reintegration initiatives.


Asunto(s)
Bienestar del Animal , Elefantes , Animales , Elefantes/fisiología , Sudáfrica , Conducta Animal/fisiología , Femenino , Masculino , Animales Salvajes , Estaciones del Año , Conservación de los Recursos Naturales/métodos
6.
Elife ; 122024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38900028

RESUMEN

The long-trunked elephantids underwent a significant evolutionary stage characterized by an exceptionally elongated mandible. The initial elongation and subsequent regression of the long mandible, along with its co-evolution with the trunk, present an intriguing issue that remains incompletely understood. Through comparative functional and eco-morphological investigations, as well as feeding preference analysis, we reconstructed the feeding behavior of major groups of longirostrine elephantiforms. In the Platybelodon clade, the rapid evolutionary changes observed in the narial region, strongly correlated with mandible and tusk characteristics, suggest a crucial evolutionary transition where feeding function shifted from the mandible to the trunk, allowing proboscideans to expand their niches to more open regions. This functional shift further resulted in elephantids relying solely on their trunks for feeding. Our research provides insights into how unique environmental pressures shape the extreme evolution of organs, particularly in large mammals that developed various peculiar adaptations during the late Cenozoic global cooling trends.


The elephant's trunk is one of the most efficient food-gathering organs in the animal kingdom. From large branches to thin blades of grass, it can coil around and bring many types of vegetation to the animals' strong, short mandibles. This versatility allows elephants to thrive in a range of environments, including grasslands. Trunks are not the only spectacular feature to emerge in Proboscideans, the family of which elephants are the only surviving group. During the early and middle Miocene (between 23 to 11.6 million years ago), many of these species had dramatically elongated lower jaws; how and why this trait emerged then disappeared is poorly understood. The role that lengthened mandibles and trunks played during feeding also remains unclear. To address these questions, Li et al. focused on Platybelodon, Choerolophodon and Gomphotherium, which belong to three Proboscidean families that roamed Northern China between 17 and 15 million years ago. Each had elongated lower jaws, but with strikingly distinct lengths and morphologies. Chemical analyses on enamel samples helped determine which habitat the families occupied, while mathematical modelling revealed how their mandibles tackled different types of plants. Trunk shape was assessed via analyses of the nasal region. The results suggest that Choerolophodon had mandibles better suited for processing branches and a short, 'primitive' trunk. Gomphotherium sported a versatile jaw that could handle both grass and trees, as well as a rather 'elephant-like' trunk. The jaw of Platybelodon seemed well-adapted to cut grass, and remarkable bone structures point towards a long, strong and flexible trunk. While modern elephants fully depend on their trunks to eat, morphological constraints suggest that, in these species, the appendage only served to assist feeding (e.g., by pressing down on branches). All families shared an environment that included grasslands and forests, but analyses suggest that, for a period, Choerolophodon favored relatively closed habitats while Platybelodon spread into grasslands and Gomphotherium navigated both landscapes. This suggests that the evolution of long, strong and flexible trunks is tightly associated with grazing. About 14 million years ago, a global cooling event led to grasslands expanding worldwide. The fossil record shows the mandibles of Proboscideans starting to shorten after this period, including in the descendants of Gomphotherium that would give rise to modern elephants. The work by Li et al. sheds light onto these evolutionary processes, and the environmental pressures which helped shape the trunk.


Asunto(s)
Evolución Biológica , Elefantes , Conducta Alimentaria , Mandíbula , Animales , Mandíbula/anatomía & histología , Mandíbula/fisiología , Conducta Alimentaria/fisiología , Elefantes/fisiología , Elefantes/anatomía & histología , Fósiles , Filogenia
7.
Sci Rep ; 14(1): 14768, 2024 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926469

RESUMEN

Hypervariable region sequencing of the 16S ribosomal RNA (rRNA) gene plays a critical role in microbial ecology by offering insights into bacterial communities within specific niches. While providing valuable genus-level information, its reliance on data from targeted genetic regions limits its overall utility. Recent advances in sequencing technologies have enabled characterisation of the full-length 16S rRNA gene, enhancing species-level classification. Although current short-read platforms are cost-effective and precise, they lack full-length 16S rRNA amplicon sequencing capability. This study aimed to evaluate the feasibility of a modified 150 bp paired-end full-length 16S rRNA amplicon short-read sequencing technique on the Illumina iSeq 100 and 16S rRNA amplicon assembly workflow by utilising a standard mock microbial community and subsequently performing exploratory characterisation of captive (zoo) and free-ranging African elephant (Loxodonta africana) respiratory microbiota. Our findings demonstrate that, despite generating assembled amplicons averaging 869 bp in length, this sequencing technique provides taxonomic assignments consistent with the theoretical composition of the mock community and respiratory microbiota of other mammals. Tentative bacterial signatures, potentially representing distinct respiratory tract compartments (trunk and lower respiratory tract) were visually identified, necessitating further investigation to gain deeper insights into their implication for elephant physiology and health.


Asunto(s)
Bacterias , Elefantes , Microbiota , ARN Ribosómico 16S , Animales , Elefantes/microbiología , Elefantes/genética , ARN Ribosómico 16S/genética , Bacterias/genética , Bacterias/clasificación , Microbiota/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Sistema Respiratorio/microbiología , Animales de Zoológico/microbiología , Análisis de Secuencia de ADN/métodos , Animales Salvajes/microbiología , Filogenia
8.
Anim Genet ; 55(4): 621-643, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38923598

RESUMEN

The African savanna elephant (Loxodonta africana) is the largest terrestrial animal on Earth and is found primarily in Southern and Eastern Africa. It is a hindgut, colonic fermenter and subsists on a diet of raw plant materials found in its grazing area. In this study the bacterial, archaeal and fungal populations of seven African savanna elephant fecal metagenomes were first characterized using amplicon sequencing. On the genus level it was observed that the p-1088-a5 gut group in the bacteriome, Methanocorpusulum and Methanobrevibacter in the archaeome and Alternaria, Aurobasidium, Didymella and Preussia in the mycome, predominated. Subsequently, metagenomic shotgun sequencing was employed to identify possible functional pathways and carbohydrate-active enzymes (CAZymes). Carbohydrate catabolic pathways represented the main degradation pathways, and the fecal metagenome was enriched in the glycohydroside (GH) class of CAZymes. Additionally, the top GH families identified - GH43, GH2, GH13 and GH3 - are known to be associated with cellulytic, hemicellulytic and pectolytic activities. Finally, the CAZymes families identified in the African savanna elephant were compared with those found in the Asian elephant and it was demonstrated that there is a unique repository of CAZymes that could be leveraged in the biotechnological context such as the degradation of lignocellulose for the production of second-generation biofuels and energy.


Asunto(s)
Bacterias , Elefantes , Heces , Microbioma Gastrointestinal , Metagenoma , Animales , Elefantes/genética , Elefantes/microbiología , Heces/microbiología , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificación , Archaea/genética , Archaea/clasificación , Metagenómica , Hongos/genética , Hongos/clasificación
9.
J Zoo Wildl Med ; 55(2): 430-435, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38875199

RESUMEN

An understanding of species-specific vitamin D metabolism and its role in calcium homeostasis is essential for correct diet formulation and development of husbandry protocols for managed nondomestic species. This study documented serum vitamin D metabolites and other analytes involved in calcium homeostasis in Asian elephants (Elephas maximus) managed at a latitude similar to their wild natural habitat. Serum values for 33 elephants managed at a low latitude were measured in the peak of summer, revealing low vitamin D2 (25(OH)D2 2.3 ± 0.6 ng/ ml and 24,25(OH)2D2 2.17 ± 0.52 ng/ml) and nondetectable vitamin D3. Serum minerals (calcium, phosphorus, magnesium), ionized calcium, and parathyroid hormone were within normal reported ranges. In comparison with previously reported values in elephants managed at a high latitude, 25(OH)D2 (P < 0.001), 24,25(OH)2D2 (P = 0.001), and magnesium (P = 0.013) were significantly lower, and parathyroid hormone was significantly higher (P < 0.001). The lack of D3 production during ample sun exposure at a low latitude suggests that Asian elephants are incapable of cutaneous photobiosynthesis of vitamin D, and that low serum D2 is normal for this species.


Asunto(s)
Biomarcadores , Calcio , Elefantes , Vitamina D , Animales , Elefantes/sangre , Elefantes/fisiología , Calcio/sangre , Vitamina D/sangre , Biomarcadores/sangre , Femenino , Masculino , Homeostasis , Animales de Zoológico
10.
Nat Ecol Evol ; 8(7): 1353-1364, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38858512

RESUMEN

Personal names are a universal feature of human language, yet few analogues exist in other species. While dolphins and parrots address conspecifics by imitating the calls of the addressee, human names are not imitations of the sounds typically made by the named individual. Labelling objects or individuals without relying on imitation of the sounds made by the referent radically expands the expressive power of language. Thus, if non-imitative name analogues were found in other species, this could have important implications for our understanding of language evolution. Here we present evidence that wild African elephants address one another with individually specific calls, probably without relying on imitation of the receiver. We used machine learning to demonstrate that the receiver of a call could be predicted from the call's acoustic structure, regardless of how similar the call was to the receiver's vocalizations. Moreover, elephants differentially responded to playbacks of calls originally addressed to them relative to calls addressed to a different individual. Our findings offer evidence for individual addressing of conspecifics in elephants. They further suggest that, unlike other non-human animals, elephants probably do not rely on imitation of the receiver's calls to address one another.


Asunto(s)
Elefantes , Vocalización Animal , Elefantes/fisiología , Animales , Masculino , Femenino , Conducta Social
13.
PLoS One ; 19(5): e0301529, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38743734

RESUMEN

African elephants have a wide range of abilities using their trunk. As a muscular hydrostat, and thanks to the two finger-like processes at its tip, this proboscis can both precisely grasp and exert considerable force by wrapping. Yet few studies have attempted to quantify its distal grasping force. Thus, using a device equipped with force sensors and an automatic reward system, the trunk tip pinch force has been quantified in five captive female African savanna elephants. Results showed that the maximum pinch force of the trunk was 86.4 N, which may suggest that this part of the trunk is mainly dedicated to precision grasping. We also highlighted for the first time a difference in force between the two fingers of the trunk, with the dorsal finger predominantly stronger than the ventral finger. Finally, we showed that the position of the trunk, particularly the torsion, influences its force and distribution between the two trunk fingers. All these results are discussed in the light of the trunk's anatomy, and open up new avenues for evolutionary reflection and soft robot grippers.


Asunto(s)
Elefantes , Animales , Elefantes/fisiología , Femenino , Torso/fisiología , Torso/anatomía & histología , Dedos/fisiología , Dedos/anatomía & histología , Fuerza de la Mano/fisiología , Fenómenos Biomecánicos
14.
PLoS One ; 19(5): e0300373, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38696403

RESUMEN

Captive and domestic animals are often required to engage in physical activity initiated or organised by humans, which may impact their body temperature, with consequences for their health and welfare. This is a particular concern for animals such as elephants that face thermoregulatory challenges because of their body size and physiology. Using infrared thermography, we measured changes in skin temperature associated with two types of physical activity in ten female Asian elephants (Elephas maximus) at an eco-tourism lodge in Nepal. Six elephants took part in an activity relatively unfamiliar to the elephants-a polo tournament-and four participated in more familiar ecotourism activities. We recorded skin temperatures for four body regions affected by the activities, as well as an average skin temperature. Temperature change was used as the response variable in the analysis and calculated as the difference in elephant temperature before and after activity. We found no significant differences in temperature change between the elephants in the polo-playing group and those from the non-polo playing group. However, for both groups, when comparing the average skin body temperature and several different body regions, we found significant differences in skin temperature change before and after activity. The ear pinna was the most impacted region and was significantly different to all other body regions. This result highlights the importance of this region in thermoregulation for elephants during physical activity. However, as we found no differences between the average body temperatures of the polo and non-polo playing groups, we suggest that thermoregulatory mechanisms can counteract the effects of both physical activities the elephants engaged in.


Asunto(s)
Elefantes , Temperatura Cutánea , Animales , Elefantes/fisiología , Femenino , Temperatura Cutánea/fisiología , Condicionamiento Físico Animal/fisiología , Temperatura Corporal/fisiología , Regulación de la Temperatura Corporal/fisiología , Termografía/métodos
15.
Ecol Appl ; 34(5): e2975, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38747033

RESUMEN

Fire and herbivory have profound effects on vegetation in savanna ecosystems, but little is known about how different herbivore groups influence vegetation dynamics after fire. We assessed the separate and combined effects of herbivory by cattle and wild meso- and megaherbivores on postfire herbaceous vegetation cover, species richness, and species turnover in a savanna ecosystem in central Kenya. We measured these vegetation attributes for five sampling periods (from 2013 to 2017) in prescribed burns and unburned areas located within a series of replicated long-term herbivore exclosures that allow six different combinations of cattle and wild meso- and megaherbivores (elephants and giraffes). Vegetation cover (grasses, mainly) and species richness were initially reduced by burning but recovered by 15-27 months after fire, suggesting strong resilience to infrequent fire. However, the rates of recovery differed in plots accessible by different wild and domestic herbivore guilds. Wildlife (but not cattle) delayed postfire recovery of grasses, and the absence of wildlife (with or without cattle) delayed recovery of forbs. Herbivory by only cattle increased grass species richness in burned relative to unburned areas. Herbivory by cattle (with or without wildlife), however, reduced forb species richness in burned relative to unburned areas. Herbivory by wild ungulates (but not cattle) increased herbaceous species turnover in burned relative to unburned areas. Megaherbivores had negligible modifying effects on these results. This study demonstrates that savanna ecosystems are remarkably resilient to infrequent fires, but postfire grazing by cattle and wild mesoherbivores exerts different effects on recovery trajectories of herbaceous vegetation.


Asunto(s)
Elefantes , Incendios , Pradera , Herbivoria , Animales , Bovinos/fisiología , Kenia , Elefantes/fisiología , Jirafas/fisiología , Poaceae/fisiología , Biodiversidad
16.
Environ Manage ; 74(1): 52-72, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38753052

RESUMEN

Landscape governance challenges, particularly in peri-urban contexts like the Bannerghatta National Park (BNP) region in South India, exemplify 'wicked' problems due to their inherent complexities. These challenges arise from a mix of conflicting interests, policy ambiguities, and sociocultural dynamics, which often blur the definition of problems and hinder effective solutions. Despite apparent options for resolution, stakeholder disagreements and deep uncertainties about implementation strategies complicate governance. This study, therefore, has two broad objectives. The first objective is to analyze the local discourses surrounding planned policy interventions around the BNP region in South India. Based on the findings, the second objective is to draw insights for sustainable natural resource governance research and practice. We applied Q-methodology to understand the discourses that underpin various conflicts in the rapidly urbanizing elephant corridor at BNP. We elicited information on how various local actors frame solutions to current collective action challenges in the BNP landscape and their perspectives on the proposed eco-sensitive zone notification, as well as the functioning of current policy interventions concerning conservation and development. The study uncovers the micropolitics and power regimes underpinning various natural resource governance challenges and demonstrates the utility of the Q-methodology in bringing diverse perspectives together in response to 'wicked' governance challenges.


Asunto(s)
Conservación de los Recursos Naturales , Elefantes , Parques Recreativos , India , Conservación de los Recursos Naturales/métodos , Animales
17.
Commun Biol ; 7(1): 472, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724671

RESUMEN

Many species communicate by combining signals into multimodal combinations. Elephants live in multi-level societies where individuals regularly separate and reunite. Upon reunion, elephants often engage in elaborate greeting rituals, where they use vocalisations and body acts produced with different body parts and of various sensory modalities (e.g., audible, tactile). However, whether these body acts represent communicative gestures and whether elephants combine vocalisations and gestures during greeting is still unknown. Here we use separation-reunion events to explore the greeting behaviour of semi-captive elephants (Loxodonta africana). We investigate whether elephants use silent-visual, audible, and tactile gestures directing them at their audience based on their state of visual attention and how they combine these gestures with vocalisations during greeting. We show that elephants select gesture modality appropriately according to their audience's visual attention, suggesting evidence of first-order intentional communicative use. We further show that elephants integrate vocalisations and gestures into different combinations and orders. The most frequent combination consists of rumble vocalisations with ear-flapping gestures, used most often between females. By showing that a species evolutionarily distant to our own primate lineage shows sensitivity to their audience's visual attention in their gesturing and combines gestures with vocalisations, our study advances our understanding of the emergence of first-order intentionality and multimodal communication across taxa.


Asunto(s)
Comunicación Animal , Elefantes , Gestos , Vocalización Animal , Animales , Elefantes/fisiología , Femenino , Masculino , Vocalización Animal/fisiología , Conducta Social
18.
PeerJ ; 12: e16746, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38562998

RESUMEN

Identifying suitable habitats and conserving corridors are crucial to the long-term conservation of large and conflict-prone animals. Being a flagship species, survival of Asian elephants is threatened by human-induced mortality and habitat modification. We aimed to assess the habitat suitability and connectivity of the Asian elephant Elephas maximus Linnaeus, 1758 habitat in the state of Odisha in eastern India. We followed the ensemble of spatial prediction models using species presence data and five environmental variables. We used least-cost path and circuit theory approaches to identify the spatial connectivity between core habitats for Asian elephants. The results revealed that normalized difference vegetation index (NDVI; variable importance 42%) and terrain ruggedness (19%) are the most influential variables for predicting habitat suitability of species within the study area. Our habitat suitability map estimated 14.6% of Odisha's geographical area (c. 22,442 km2) as highly suitable and 13.3% (c. 20,464 km2) as moderate highly suitable. We identified 58 potential linkages to maintain the habitat connectivity across study area. Furthermore, we identified pinch points, bottlenecks, and high centrality links between core habitats. Our study offers management implications for long-term landscape conservation for Asian elephants in Odisha and highlights priority zones that can help maintain spatial links between elephant habitats.


Asunto(s)
Elefantes , Animales , Humanos , Ecosistema , Ambiente , India
19.
Front Immunol ; 15: 1329820, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38590526

RESUMEN

The immune system of Asian elephants (Elephas maximus) is poorly studied, compared to that of livestock, rodents or humans. The innate immune response has become a focus of interest in relation to Elephant endotheliotropic herpesviruses (EEHVs). EEHVs cause a fatal hemorrhagic disease (EEHV-HD) and are a significant threat to captive Asian elephant populations worldwide. Similar to other herpesvirus infections, nearly all animals become infected, but only some develop disease. As progression to EEHV-HD is often acute, a robust innate immune response is crucial to control EEHV infections. This is invariably true of the host in the first instance, but it can also potentially be modulated by intervention strategies. Here, two immunostimulant veterinary medicinal products, authorized for use in domestic species, were tested for their ability to induce innate anti-viral immune responses in Asian elephant blood cells. Sequence data were obtained for a range of previously unidentified Asian elephant immune genes, including C-X-C motif chemokine ligand 10 (CXCL10), interferon stimulated gene 15 (ISG15) and myxovirus GTPase 1 (Mx1), and were employed in the design of species-specific qPCR assays. These assays were subsequently used in analyses to determine fold changes in gene expression over a period of 24 hours. This study demonstrates that both immunostimulant medications are capable of inducing significant innate anti-viral immune responses which suggests that both could be beneficial in controlling EEHV infections in Asian elephants.


Asunto(s)
Elefantes , Infecciones por Herpesviridae , Herpesviridae , Humanos , Animales , Ovinos , Elefantes/genética , ADN Bacteriano , Células Sanguíneas , Inmunidad Innata , Plásmidos , Inmunización , Adyuvantes Inmunológicos , Expresión Génica
20.
PLoS One ; 19(4): e0299689, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38656936

RESUMEN

The use of elephant ivory as a commodity is a factor in declining elephant populations. Despite recent worldwide elephant ivory trade bans, mammoth ivory trade remains unregulated. This complicates law enforcement efforts, as distinguishing between ivory from extant and extinct species requires costly, destructive and time consuming methods. Elephant and mammoth ivory mainly consists of dentine, a mineralized connective tissue that contains an organic collagenous component and an inorganic component of calcium phosphate minerals, similar in structure to hydroxyapatite crystals. Raman spectroscopy is a non-invasive laser-based technique that has previously been used for the study of bone and mineral chemistry. Ivory and bone have similar biochemical properties, making Raman spectroscopy a promising method for species identification based on ivory. This study aimed to test the hypothesis that it is possible to identify differences in the chemistry of mammoth and elephant ivory using Raman spectroscopy. Mammoth and elephant tusks were obtained from the Natural History Museum in London, UK. Included in this study were eight samples of ivory from Mammuthus primigenius, two samples of carved ivory bangles from Africa (Loxodonta species), and one cross section of a tusk from Elephas maximus. The ivory was scanned using an inVia Raman micro spectrometer equipped with a x50 objective lens and a 785nm laser. Spectra were acquired using line maps and individual spectral points were acquired randomly or at points of interest on all samples. The data was then analysed using principal component analysis (PCA) with use of an in-house MATLAB script. Univariate analysis of peak intensity ratios of phosphate to amide I and III peaks, and carbonate to phosphate peaks showed statistical differences (p<0.0001) in the average peak intensity ratios between Mammuthus primigenius, Loxodonta spp. and Elephas maximus. Full width at half maximum hight (FWHM)analysis of the phosphate peak demonstrated higher crystal maturity of Mammuthus primigenius compared to living elephant species. The results of the study have established that spectra acquired by Raman spectroscopy can be separated into distinct classes through PCA. In conclusion, this study has shown that well-preserved mammoth and elephant ivory has the potential to be characterized using Raman spectroscopy, providing a promising method for species identification. The results of this study will be valuable in developing quick and non-destructive methods for the identification of ivory, which will have direct applications in archaeology and the regulation of international trade.


Asunto(s)
Elefantes , Espectrometría Raman , Animales , Espectrometría Raman/métodos , Mamuts , Extinción Biológica , Análisis de Componente Principal , Conservación de los Recursos Naturales/métodos , Animales Salvajes , Fósiles , Comercio de Vida Silvestre
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